The present invention relates to a suction module for a hand-held power tool.
A suction module is known from EP 2599584 A1. The suction module has a collecting container for dust and a motor-driven fan wheel, which carries dust-laden air from an intake nozzle to the collecting container. The suction module covers both the drill bit as well as the drill hole, as a result of which it is difficult for a user to detect interruptions in the drilling operation.
The suction module according to the invention for a hand-held power tool has a motor-driven fan wheel, an intake channel for drawing in dust-laden air and a collecting container for dust. A flow sensor has a sensor surface formed of plastic, which is arranged in the intake channel; an electric field meter, which faces the sensor surface, for determining the electrostatic field strength at the sensor surface; and an evaluation unit for determining a flow rate of dust-laden air on the basis of the determined electrostatic field strength. During proper drilling operations, a minimum quantity of dust-laden air per unit of time is accrued. If the effective flow rate is less, this points to a possible problem. When taking into account the flow rate or its changes, a malfunction can be prevented by the user, the suction module, or the hand-held power tool.
The following description explains the invention using illustrative embodiments and drawing.